Control apparatus



Feb

. 12 1935. L. G. RILEY CONTROL APPARATUS Filed April 22, 1933 3Sheets-Sheet 1 WITNESSES:

INVENTOR Lynn 6. BYey ATTOR Y Feb. 12, 1935. L. G. RILEY 1,991,229

CONTROL APPARATUS Filed April 22, 19:53

5-Sheets-$heet 2 WITNESSES: INVENTOR 65% Lynn 6, Riley Feb. 12, 1935. REY 1,991,229

CONTROL APPARATUS Filed April 22, 1933 3 Sheets-Sheet 3 Patented Feb.12, 1935 UNITED STATES CONTROL APPARATUS Lynn G. Riley, Pittsburgh, Pa.,assignor to Westinghouse Electric & Manufacturing Company,

East Pittsburgh, Pa., sylvania a corporation of Penn- Application April22, 1933, Serial No. 667,367

13 Claims.

My invention relates, generally, to control apparatus and moreparticularly to apparatus for controlling the acceleration of streetcars, trolley buses and the like.

In accordance with the teachings of the prior art, the acceleration ofelectrically-propelled vehicles has been controlled by connectingresistors in series with the propelling motors of the vehicles tocontrol the current supplied the motors. The resistors are shunted fromthe motor circuits step-by-step either by means of drum controllershaving sliding contact members or by means of unit switches which areoperated either electrically or by air pressure. Drum controllers arefairly satisfactory when the motor current is small and a relatively fewsteps of acceleration are required, but they are'not capable ofcontrolling high values of current and the drums become excessive insize if a large number of steps are provided. Unit switches have beendeveloped which have high interrupting capacities and, at present,switches of this type are utilized on practically all street cars tocontrol the acceleration.

However, when a large number of steps of resistance are provided, inorder to increase the smoothness of acceleration, the unit switchesrequire a large amount of space and greatly increase the weight and costof the control equipment. In order for the street car to successfullycompete with other modes of transportation, it is necessary to increasethe rate of acceleration and the smoothness of control, and at the sametime decrease the cost of operation.

An object of my invention, generally stated, is to provideacceleration-control apparatus which shall be light in weight, simpleand efficient in operation and which may be readily and economicallymanufactured and installed.

A more specific object of my invention is to provide for shunting aplurality of resistor sections in sequential relation without utilizingsliding contact members.

Another object of my invention is to provide acceleration-controlapparatus which shall be ex-v tremely compact and which will occupy aminimum amount of space.

A still further object of my invention is to provide resistor-shuntingapparatus in which the resistor elements are connected directly tocontact members which shunt the respective resistor elements, therebymaking cable connections unnecessary. I

Other objects of my invention ill be explained fully hereinafter or willbe apparent to those skilled in the art.

According to one embodiment of my invention, an accelerator orcontroller is provided in which a plurality of spring-mounted contactmembers are successively pressed against a circular busbar by means of aspring-loaded roller. As each contact member is pressed against thebus-bar, a small step'of resistance is shunted from an electricalcircuit, thereby increasing the current in the circuit. The actuatingroller is carried on a rotating arm which may be driven either by areversible pilot motor or by an air engine. The speed of the pilot motormay be varied to permit the selection of several different rates ofacceleration as desired by the operator to suit operating conditions.The resistor sections are assembled on the outside and above theaccelerator frame and are connected directly to the contact members,thereby making separate cable connections between the control apparatusand the resistors unnecessary.

For a fuller understanding of the nature and scope of the invention,reference may be had to the following detailed description, taken inconjunction with the accompanying drawings, in which:

Figure 1 is a top plan view of control apparatus constructed inaccordance with my invention;

Fig. 2 is a bottom plan view of the apparatus, and

Fig. 3 is an enlarged view, partially in section and partially inelevation of the apparatus shown in Figs. 1 and 2.

Referring to the drawings, and particularly to Figs. 2 and 3, theaccelerator illustrated comprises a plurality of contact members 10which are resiliently mounted on the inside of a ring 11 composed ofinsulating material. The ring 11 is mounted in a panel 12 which may besupported in a car body (not shown) in any suitable manner.

As shown, the contact members 10 are carried by leaf springs 13 whichare secured to the ring 11 by bolts 14. The contact members 10 are sodisposed that they may be pressed outwardly to engage a circular bus-bar15 mounted on the outside of the ring 11 and secured thereto by screwbolts 16. The bus-bar 15 may be composed of copper, or other materialsuitable for conducting electric current, and, as shown, the bar extendsbelow the bottom of the ring 11 to permit the contact members 10 to bepressed into engagement therewith in a manner to be more fully describedhereinafter. A cable connection 20 is provided for connecting thebus-bar in an electrical circuit.

As shown, a plurality of resistor elements 1'7 are mounted outside andabove the ring 11. The resistor elements 17 are supported by eshapedarms 18 which are secured in a ring Iii/composed of insulating material.The ring 19is mounted above a circular metal plate 21 which covers thering 11, by means of extension bolts 22, the lower ends of which aresecured to the plate 21.

Insulating bushings 23 and 24 are placed between the ring 19 and thebolts 22, as shown, to

insure that the resistor elements 17 will be prop erly insulated fromthe bolts 22 and the cover plate 21. I If it is desired to provide moreresistor elements than can be mounted around the outlnside of the ringin the space above the plate 21. All of the resistor elements 17 may beconnected in series if desired, or they may be divided into two or moregroups, the elements in each group being connected in series.

In order that the resistor may be shunted stepby-step, each section orelement of the resistor is connected to one of the contact members 10 bymeans of a stud 25, which extends through the ring 11, and is connectedto the upper end of the spring 13 which carries the contact member 10.The resistor sections are connected to the studs 25 by means of clamps30. When each contact member is pressed against the circular bus bar 15,as will be described hereinafter, the section of the resistor connectedto that contact member is shunted from the electrical circuit in whichthe resistor is connected.

A roller 26, which is of suillcient circumference to engage two of thecontact members 10 at the same time and may be composed of a suitableinsulating material, is provided for pressing the contact members intoengagement with the copper ring 15. The roller 26 is carried by abifurcated rotating arm 27, driven by a motor 28 and is mounted on across-arm 29, one end of which is pivotally connected to one fork 31 ofthe bifurcated arm 27. The other end of the cross arm 29 is slidablymounted in the other for]: 32 of the arm 27 and the roller 26 is forcedoutwardly by a spring 33. The roller 26 is mounted on the cross arm 29by means of a ball bearing 34, thereby reducing friction.

The rotating arm 27 is secured to the lower end of a vertical shaft 35,which is supported in a casting member 36 by two ball or roller bearings37 and=38. The casting member 36 is secured to the bottom side of theplate 21 by three bolts 39. The shaft 35 is rotated by a gearwheel 41driven by an enclosed worm drive 42 which is connected to the shaft 43of the motor 28 by means of a flexible coupling 44. The gear wheel 41 isalso enclosed in a metal casing 45 to provide for proper lubrication ofthe driving m It will be seen that the contact members 10 aresuccessively pressed into engagement with the circular bar 15 as theroller 26 is actuated around the circular row of contact members. Aspreviously explained, each contact member 10 is connected to a sectionof the resistorl'l. Therefore resistor 17 may be so conby-step when theroller 26 is driven in one direc tion around the circular row of contactmembers, thereby decreasing the amount of resistance in the electricalcircuit. When the roller 26 is driven in the opposite direction. theamount of resistance connected in the circuit is increased. Theoperation of the motor 28 may be controlled to stop the roller 26 at anydesired position and the rate of travel of the roller may be varied byvarying the speed of the motor 28. In this manner the rate ofacceleration of the propelling motors ofa street car, or othe electricvehicle may be readily controlled.

It will be observed that the contact members 10 are provided with aspherical or rounded surface place between the contact member 10 and thebar 15, as the contact member engages and disengages the bar, to keepthe contacting surfaces clean, a non-flexible plate is mounted on each fthe contact members 10, the flexible spring leaves 13 being interposedbetween the plate 40 and the contact member.

As shown in Fig. 3, the plate 40 extends upwardly a' sufilcient distanceto permit the roller 26 to engage the plate above the contact member. Itwill thus be seen that the springs 13 are deflected, when the roller 26engages the plate 40, in a manner to produce a slight movement, in avertical direction, between the contact member and the bus bar.

Referring particularly to Fig. 2, it will be observed that the roller 26first engages one corner 5 of the plate 40 on each of the contactmembers as the roller is driven around the circular row of contactmembers The leaf springs 13, which support the contact members, are.therefore, twisted a slight amount as the contact member is actuatedtoward the bus bar, thereby producing a slight movement, in a horizontaldirection, between the contact member and the bus bar. In this manner, adefinite rubbing action is caused to take place between the contactmembers and the bus bar, thereby maintaining the contacting surfacesclean and free of oxidized matter, which prolongs the life of thecontact members.

In order that certain of the contact members 10 may be actuated intoengagement with the bus-bar 15 independently of the roller 26, a plungerarm 46 is disposed to be actuated by a cam 47 on the shaft 35. Theplunger arm 46 is normally retracted by a spring 48, disposed in ahousing 49 which is secured to the casting member 36. When the end ofthe plunger rod is engaged by the cam 4'7, the plunger 46, which isdisposed opposite one of the contact supporting springs 13, engages thespring to press one of the contact members 10 against the bus-bar 15.

It will be understood that the cam 47 may be so shaped and positioned onthe shaft 35, that the contact member actuated by the plunger 46 may beretained in engagement with the bus bar 15 during any desired period oftime. Additional cams 51, 52 and 53 are provided on the shaft 35, whichmay be utilized to operatelimit switches (not shown) for controlling theoperation of the motor 28, also other plungers, similar to the oneshown, may be provided if desired.

A metal cover 54 is mounted underneath the panel 12 for enclosing thecontact members 10, the roller 26 and its operating mechanism. A feltwasher 55 is interposed between the cover 54 and the panel 12 to excludedirt and moisture from the mechanism. The cover is mounted on the panelby means of hinges 56 and 57 and is retained closed by. wing-nuts 58 and59. It may be readily lowered to permit inspection of the apparatus byremoving the nuts 58 and 50 and permitting the cover to swing about itshinges 56 and 57. It will thus be seen that all moving parts of theapparatus and also the resistor shunting contact members are completelyenclosed and protected from dirt and moisture. From the foregoingdescription it will be appareat that I have provided control apparatusparticularly adapted for controlling the acceleration ofthe propellingmotors of electric Vehicles. although it is not limited to controllingmotors of thistype. Sincealarge is obtained; The apparatus hereindescribed light in weight and compact, thereby occupying a small amountof space in a vehicle.

I do not desire to be restricted to the specific embodiment of myinvention herein shown and described, since it is evident that it may bechanged and modified without departing from the spirit and scope of myinvention as definedin the appended claims.

I claim as my invention:

1. In control apparatus, in combination, a re-, sistor having aplurality of sections, a stationary bus-bar comprising an arc of acircle, a plurality of resiliently mounted contact members disposed toengage the bus-bar to shunt the resistor sections, and means disposed tomove concentrically within the bus-bar for pressing the contact membersinto engagement withthe bus-bar.

2. In control apparatus, in combination, a resistor having a pluralityof sections, a stationary bus-bar comprising an arc of a circle, aplurality of resiliently mounted contact members disposed to engage thebus-bar to shunt the resistor sections step-by-step, a rotatable memberfor pressing the contact members into engagement with the bus-bar insuccessive relation, and means for operating said rotatable memberconcentrically along the bus-bar.

3. In control apparatus, in combination, a resistor having a pluralityof sections, a circular bus-bar, a plurality of resiliently mountedcontact members mounted along the circular bus-bar and disposed toengage the bar to shunt the resistor sections, a rotatable member foractuating the contact members into engagement with the busbar, and meansfor operating said rotatable member.

4. In control apparatus, in combination, a resistor having a pluralityof sections, a circular bus-bar, a plurality on spring mounted contactmembers mounted inside of the circular bus-bar and disposed to beactuated into engagement with the bar to shunt the resistor sections, arotatable member mounted inside oi the contact members and disposed toactuate the contact members into engagement with the bus-bar, and meansfor operating the rotatable member.

5. In control apparatus, in combination, aresistor having a pluralitycofsections, a circular bus-bar, a plurality of spring mounted contactmembers disposed to engage the bus-bar to shunt the resistorsections, aresiliently mounted roller for pressing the contact members intoengagement with the bus-bar, and means for actuating the roller.

- 6. In control apparatus, in combination, a resistor having a pluralityof sections, a circular bus-bar, a plurality of spring mounted contactmembers disposed to engage the bus-bar to shunt the resistor sections, aresiliently mounted roller' for pressing the contact membersintoengagement with the bus-bar, a rotatable arm for supporting the roller,and means for driving the rotatable arm.

'1. In control apparatus, in combination, a resistor having a pluralityof sections, a circular bus-bar, a plurality of spring mounted contactmembers disposed to engage the bus-bar to shunt the resistor sections, aresiliently mounted roller for successively pressing the contact membersinto engagement with the-bus-bar, a bifurcated arm for supporting theroller, and means for rotating the arm.

8. In control apparatus, in combination, a re: sistor having a pluralityof sections, a circular bus-bar, a plurality of spring mounted contactmembers disposed to engage the bus-bar to shunt the resistor sections, aresiliently mounted roller ior pressing the contact members intoengagement with the bus-bar, a rotatable arm for supporting the roller,means for driving the rotatable arm, and plunger means for actuatingcertain of the contact members into engagement with the bus-bar during apredetermined period of time.

- 9. In control apparatus, in combination, a resistor having a pluralityof sections, a circular bus-bar, a plurality of spring mounted contactmembers disposed to engage the bus-bar to shunt the resistor sections, aresiliently mounted roller for pressing the contact members intoengagement with the bus-bar, a rotatable arm for supporting the'roller,means for driving the rotatable arm, plunger means for actuating certainof the contact members into engagement with the bus-bar during apredetermined period of time, and cam means for operating said plungermeans.

10. In control apparatus, in combination, a plurality of resistorelements, a circular bus-bar, a plurality of contact members disposed toengage the bus-bar to shunt the resistor elements, a spring element forsupporting each of said contact members, stud members for connecting theresistor elements to the spring elements, rotat able means for pressingthe contact members into engagement with the bus-bar, and means foractuating said rotatable means.

11. In' control apparatus, in combination, a plurality of verticallymounted resistor elements disposed in circular arrangement, a circularbusbar disposed below the resistor elements, a plurality of cont-actmembers disposed to be actuated into engagement with the bus-bar toshunt the resistor elements, a spring element for supporting each ofsaid contact members, stud members for connecting the resistor elementsto the spring elements, rotatable means for pressing the contact membersinto engagement with the bus-bar, and means for actuating said rotatablemeans.

12. In control apparatus, in combination, a circular bus-bar, aplurality of contact members having a rounded surface disposed to engagethe bus-bar to establish electrical 'circuits,-a flexible spring elementfor supporting each of said contact members, a non-flexible platemounted on each contact member, and rotatable means for actuating thecontact members into engagement with the bus bar, said rotatable meansbeing disposed to first engage one corner or the plates on the contactmembers in a manner to twist the flexible springs a slight amountthereby producing a rubbing action between thecontact members and-thebus-bar.

13. In control apparatus, in combination, a circular bus-bar, aplurality of contact mem bers having a rounded surface disposed toengage the bus-bar to establish-electrical circuits, a flexible springelement for supporting each of said contact members, a plate mounted oneach contact member and extending above the contact member, androtatable means for actuating the contact members into engagement withthe busbar, said rotatable means being disposed to engage the platesabove the center line or the contact members in a manner to produce arubbing action between the contact members and the busbar.

1mm G. am.

